package com.codejiwei.flink.practice;

import org.apache.flink.api.common.functions.FlatMapFunction;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.api.java.functions.KeySelector;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.util.Collector;

/**
 * @author jiwei
 * @description
 * @date 2023/5/15 14:04
 */
public class WordCount {
    public static void main(String[] args) throws Exception {
        Configuration conf = new Configuration();
        StreamExecutionEnvironment env = StreamExecutionEnvironment.createLocalEnvironmentWithWebUI(conf);

        DataStreamSource<String> sourceDS = env.readTextFile("E:\\workspace\\ss-flink\\src\\main\\resources\\data\\world.txt");
        sourceDS.flatMap(new FlatMapFunction<String, String>() {
            @Override
            public void flatMap(String line, Collector<String> collector) throws Exception {
                String[] words = line.split(" ");
                for (String word : words) {
                    collector.collect(word);
                }
            }
        }).map(new MapFunction<String, Tuple2<String, Long>>() {
            @Override
            public Tuple2<String, Long> map(String s) throws Exception {
                return Tuple2.of(s, 1L);
            }
        }).keyBy(new KeySelector<Tuple2<String, Long>, String>() {
            @Override
            public String getKey(Tuple2<String, Long> stringLongTuple2) throws Exception {
                return stringLongTuple2.f0;
            }
        }).sum(1)
                .print();

        env.execute("WordCount");
    }
}
